This invention relates to antennas and more particularly to a multipurpose submarine antenna.
Multipurpose submarine antennas are constructed to handle several types of radiations simultaneously. As a result, these structures have a relatively high packing density and space within the structure is at a premium. In particular, one prior art submarine antenna contains as one of its radiators a short, linearly polarized "door knob" fat monopole to handle IFF (identification friend or foe) transmissions. There is no more room within the structure to fit an antenna to receive GPS (global positioning satellite) signals and to compound the problem, the GPS signals are circularly polarized. In addition, GPS transmissions require antenna coverage for all angles in the upper hemisphere extending from +20.degree. to overhead. This means that even if one were willing to take the polarization loss of the present IFF antenna, the pattern loss would be prohibitive at high angles.